Topic: Pipe color

[DaveInTexas]

I noticed my new to me bike has 3 nicely bronzed pipes and one that is still silver (#4).
I wish I'd noticed what they were like when I bought it last month (only as a troubleshooting thing).  Maybe the silver one was a recent replacement.

One does not heat up quite as much as the others at idle, but its not the chrome one, its one of the bronz-ey ones (#3).

Is it possible to have the carbs set too lean or the timing too advanced in such a way that the engine makes too much heat and melts valves or bronzes exhaust pipes, etc if I am running only low speed and short rides in town, always below 4000rpm?

I will get it tuned up but I'd reallly like to ride a few miles to find all the bugs at once - as long as I'm not hurting it with too much heat. 
When I pulled the plugs last they were all sort of fouled, not showing signs of heat stress at all.

[csendker]

The 4-4 exhausts are notorious for rotting out as they don't heat up like a 4-2 or 4-1, thus condensation, rust, etc.  This particularly happens when you do a bunch of short hops, not allowing the pipes to come to full temp and evaporate the condensation.  And yes, individual carb set-up can impact the exhaust temperature.  Too lean and you'll run hot, cooking all sorts of stuff like your valves; that is in addition to the exhaust.  My timing was off, and I noticed it when my 1-4 pipes were running noticeably colder than the 2-3 pipes.  Of course, it was only running on 2 cylinders, so there were other obvious pointers that something was amiss.